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  <title>在数组开头插入一个或多个单元</title>
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  <div id="layout-content"><div id="function.array-unshift" class="refentry">
   <div class="refnamediv">
    <h1 class="refname">array_unshift</h1>
    <p class="verinfo">(PHP 4, PHP 5, PHP 7)</p><p class="refpurpose"><span class="refname">array_unshift</span> &mdash; <span class="dc-title">
     在数组开头插入一个或多个单元
    </span></p>

   </div>
 <div class="refsect1 description" id="refsect1-function.array-unshift-description">
  <h3 class="title">说明</h3>
  <div class="methodsynopsis dc-description">
   <span class="methodname"><strong>array_unshift</strong></span>
    ( <span class="methodparam"><span class="type">array</span> <code class="parameter reference">&$array</code></span>
   [, <span class="methodparam"><span class="type"><a href="language.pseudo-types.html#language.types.mixed" class="type mixed">mixed</a></span> <code class="parameter">$...</code></span>
  ] ) : <span class="type">int</span></div>

    <p class="para rdfs-comment">
     <span class="function"><strong>array_unshift()</strong></span> 将传入的单元插入到
     <code class="parameter">array</code> 数组的开头。注意单元是作为整体被插入的，因此传入单元将保持同样的顺序。所有的数值键名将修改为从零开始重新计数，所有的文字键名保持不变。
    </p>
   </div>

    <div class="refsect1 parameters" id="refsect1-function.array-unshift-parameters">
  <h3 class="title">参数</h3>
  <p class="para">
   <dl>

    
     <dt>
<code class="parameter">array</code></dt>

     <dd>

      <p class="para">
       输入的数组。
      </p>
     </dd>

    
    
     <dt>
<code class="parameter">...</code></dt>

     <dd>

      <p class="para">
       插入的变量。
      </p>
     </dd>

    
   </dl>

  </p>
 </div>

 <div class="refsect1 returnvalues" id="refsect1-function.array-unshift-returnvalues">
  <h3 class="title">返回值</h3>
  <p class="para">
    返回 <code class="parameter">array</code> 数组新的单元数目。
  </p>
 </div>

   
 <div class="refsect1 changelog" id="refsect1-function.array-unshift-changelog">
  <h3 class="title">更新日志</h3>
  <p class="para">
   <table class="doctable informaltable">
    
     <thead>
      <tr>
       <th>版本</th>
       <th>说明</th>
      </tr>

     </thead>

     <tbody class="tbody">
      <tr>
       <td>7.3.0</td>
       <td>
        现在可以只用一个参数来调用，之前至少需要两个参数。
       </td>
      </tr>

     </tbody>
    
   </table>

  </p>
 </div>

   
 <div class="refsect1 examples" id="refsect1-function.array-unshift-examples">
  <h3 class="title">范例</h3>
  <p class="para">
   <div class="example" id="example-6079">
    <p><strong>Example #1 <span class="function"><strong>array_unshift()</strong></span> 例子</strong></p>
    <div class="example-contents">
<div class="phpcode"><pre><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br />$queue&nbsp;</span><span style="color: #007700">=&nbsp;array(</span><span style="color: #DD0000">"orange"</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">"banana"</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">array_unshift</span><span style="color: #007700">(</span><span style="color: #0000BB">$queue</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">"apple"</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">"raspberry"</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">print_r</span><span style="color: #007700">(</span><span style="color: #0000BB">$queue</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</pre></div>
    </div>

    <div class="example-contents"><p>以上例程会输出：</p></div>
    <div class="example-contents screen">
<div class="cdata"><pre>
Array
(
    [0] =&gt; apple
    [1] =&gt; raspberry
    [2] =&gt; orange
    [3] =&gt; banana
)
</pre></div>
    </div>
   </div>
  </p>
 </div>

 <div class="refsect1 seealso" id="refsect1-function.array-unshift-seealso">
  <h3 class="title">参见</h3>
  <p class="para">
   <ul class="simplelist">
    <li class="member"><span class="function"><a href="array_shift.html" class="function" rel="rdfs-seeAlso">array_shift()</a> - 将数组开头的单元移出数组</span></li>
    <li class="member"><span class="function"><a href="array_push.html" class="function" rel="rdfs-seeAlso">array_push()</a> - 将一个或多个单元压入数组的末尾（入栈）</span></li>
    <li class="member"><span class="function"><a href="array_pop.html" class="function" rel="rdfs-seeAlso">array_pop()</a> - 弹出数组最后一个单元（出栈）</span></li>
   </ul>
  </p>
 </div>

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